Where are you from? Where did you study?I was born in Tokyo but have lived and worked on Hokkaido Island which is Japan’s northernmost and least populous region. I received my MD from Jichi Medical School, which is just outside of Tokyo. I completed my paediatric residency and fellowship on Hokkaido Island at Asahikawa Medical School. As part of my training, I spent some time practicing in a remote community that was very under-served. I was the only physician for a community of about 18,000 people.

I came to study in Toronto almost by chance. About twenty years ago, I attended a conference in former Czechoslovakia where Dr. Gideon Koren and Dr. Stuart MacLeod were speaking (both former division heads of SickKids Clinical Pharmacology and Toxicology department). After hearing my presentation, Dr. Koren convinced me to do a fellowship at SickKids and I have been here ever since. The weather on Hokkaido is similar to here – it can get pretty cold. So the winters were not a deterrent for me coming to Canada.

What are you researching right now?
My lab has both a clinical and a basic science focus. The main theme of my research is drug safety during breastfeeding. My lab is investigating things like: how are drugs entering milk? How do infants react to the presence of drugs in milk? We are also asking questions about whether the major drug metabolizing enzyme is influenced by tonicity or oxidative stress.

Who is your all-time favourite scientist and why?
Albert Einstein. I read his biography when I was a kid and we also share the same birthday. The other attraction is that I have absolutely no knowledge about his area of scientific study. I do know, however, that his ideas were revolutionary and have had a huge impact. He has influenced so many different types of thinking, from physics to philosophy.

What in your opinion is the single most important scientific breakthrough, and why?
No single important discovery happens in isolation. So much work leads up to a breakthrough, it’s a like a chain reaction. How do you accurately pin-point where it started?

What are your major interests outside of the lab?Ice hockey, I grew up playing it. I remember admiring all of the big Canadian stars like Bobby Orr. I play hockey regularly with some of my buddies from SickKids.

Why science?
I was always interested in medicine and I really like the interaction with patients. The good thing about science (compared to something like politics) is that science only cares about one thing, the truth. My name actually means “truth” in Japanese. I believe that truth brings joy.

Why SickKids?Paediatricians in Japan will tell you that SickKids is one of the top paediatric hospitals anywhere. SickKids has tremendous stature all over the world. Of course, part of the reason I came was meeting Dr. Koren and Dr. MacLeod as I mentioned earlier. What Dr. Koren didn’t tell me at the time was that they actually didn’t have the funding in place to pay me when he invited me to Canada – they had to find the money after the fact!

What is the most controversial question in your field right now?
There is some controversy right now as to why the mammary gland has a drug-transporting protein. The protein transmits small amounts of drugs through a woman’s breast milk to her infant. Basically this is the same type of protein that helps to transport waste, like urine, from your body. We don’t think of breast milk as waste, so the question remains, what is the significance of this protein’s presence? Research even suggests that these proteins increase when a woman is lactating; on the surface it’s quite puzzling. One of the theories being floated right now is that this small exposure to toxins actually helps to prepare the baby for dangers in the environment that it will encounter as it matures.